Tuesday, 10 December 2013

I’ve been having a play with the free trial of Kaleidoscope
software from Wildlife Acoustics. This was partly prompted by the courses I’ve
been running on behalf of BCT for some of the larger consultancies who generate
far more data than they can ever analyse manually, so they are very keen to
embrace automated processing software. To test it I’ve run through some 10,000
files that I’ve manually looked through so I know what’s on them. These are
mostly from a Pettersson D500x, but there are also a large number of files from
the SM2BAT+.

The basic interface is modular, in that the file conversion
utility is free. You can use this to batch process and convert .wac files to
.wav and also zero crossing files. To this you can add the Kaleidoscope viewer
(£325) or opt for the Kaleidoscope Pro version which includes the viewer and a
set of classifiers for UK bats (£755). You can download and try Kaleidoscope
pro for 15 days to try it out, which is what I did.

To start with, there has clearly been a lot of time spent on
the interface. It works nicely, is simple and does the job. One minor
irritation is that you can select an output directory that is above the data directory.
In other words, if you data is in C:\field_data, you can’t put the results
either in that directory, or in one above it such as C:\field_data\results.
They have to go into a directory at the same level or below the one you are
processing. If you are just processing files to classify them, don’t check any
of the output file formats unless you want copies of the processed files in
your results folder. With 60 GB of data to process, this can cause havoc!

If you are classifying calls, you have the option of
switching in and out any of the current 11 species classifiers. Myotis is still lumped together
(sensibly), and the newest addition is a classifier for Nathusius’ pipistrelle.
There are two classifiers for lesser horseshoe, a normal one and one for the
192 kHz recording mode where lesser horseshoe calls would be aliased.

To start, you select the directory on the left hand side of
calls you want to process. You can also
include sub-directories from this which is a nice feature meaning you can batch
process A LOT of files. You select or make an output folder on the right hand
side for the output files, select the classifiers you want to use (i.e. the
species you want to look for), hit ‘process files’ and go away for a cup of
tea, lunch or a mini-break to a top European destination depending on how many
files you need to process. For my files it took around 10-15 minutes per night
of data, which for this type of processing is very very fast. However, as this
is very CPU intensive, I couldn’t use my PC for anything else while the
processing was going on. If I did try, Kaleidoscope threw up a few file I/O
errors claiming that the file was too big to process. So best to leave it to do
its job. If you have a lot of detectors for a lot of nights, this could take
you a few days, so be mindful of that.

The output is presented as a table, but also output as a
.csv file to your selected results directory. It tells you the file name,
species ID, number of pulses and certainty of identification. You can then
click on each entry and that file opens up in the viewer which is a really nice
feature so you can check it and if necessary amend the identification. You can
also click on the column heading to sort by species to look for anything that
is not a pipistrelle. I have to say I’m not a great fan of the layout and look
of the viewer, but then I’ve used Batsound for years so am more used to that. I’m
sure you can customise the viewer to suit the look and layout you want.

So how did it fare on identification? Well, I have to say it
did pretty well considering. It’s not overly keen to classify things, which I
like. I have used other software which is intent on suggesting the most bizarre
species. Nothing too odd came out of this, and it did seem to deal quite well
with the dreaded pipistrelle social calls which other software turns into
barbastelles among other things. There was a category of ‘noID’ which is where
the software admits it can’t identify something, which again is pretty honest.

It is quite keen to pull out P. nathusii (I downloaded it with the nathusii classifier). So a P. pipistrellus with FmaxE at 41 kHz was
a nathusii, with high confidence which it clearly was not. This happened quite
a lot where groups of common pipistrelles were flying together and shifting
their call frequencies away from one another. Personally I wouldn’t take any
nathusii classification at face value without checking it manually.

It struggled with the big bats group. Obvious N. noctula were right, but some serotine/leislers FM-QCF calls were
attributed to N. noctula when they
were too high for my liking. Also some higher QCF noctule calls at 22-23 kHz
were attributed to N. leisleri when
the IPI was far too long to be leisleri.
Again, I’d like to have a look manually at all the big bat classifications.

One bizarre occurrence was that high amplitude recordings of P. pygmaeus which
had nice harmonics at 110 kHz were picked up with 70% plus confidence as lesser
horseshoes rather than pygmaeus, even
though they were lovely pygmaeus
recordings. P. auritus also cropped up a few times in the recordings but it was
usually a Myotis, so that needs
watching. It did a pretty decent job of ignoring pip social calls rather than
attributing them to something, again which is pretty good.

The software did fail to deal with recordings which had more than one species
in them, but that’s not terribly surprising.

One potentially more alarming issue was that I had about
five nights of data from inside a church which had a brown long-eared roost in
it. The software failed to find a single long-eared call even though there were
plenty of classic (weak) calls in the recordings, as well as the usual social
calls. This happened even when I turned the sensitivity up on the classifier
(there is a more accurate/more sensitive switch). I wouldn’t be happy using this to find
long-eared bats in barn conversions for example without manually going through
the data. I even edited out good long-eared recordings and put individual files
through. It wasn’t that it didn’t classify them, it just couldn’t find them.

In summary, it did a pretty good job as a pipistrelle
filter, and can be great for sorting out other species to check manually, but I’d
still want to have a look at any file that wasn’t a P. pipistrellus/pygmaeus to
check the classification. The software can save a great deal of time, and in
some larger scale surveys may be a necessity, but I would be reluctant to
accept any non-common or soprano pipistrelle identification at face value
without having a look at it first.

Wednesday, 17 July 2013

Having to potentially do a pipistrelle exclusion this summer, I thought I'd have a go at making and installing an American style bathouse on the building just to see if it worked. I used some modified plans from the Bat Conservation International (BCI) publication 'The bat house builder's handbook' to construct it. I had to adapt the plans slightly for the metric measurements so used a quarter sheet of 9mm ply and another of 12mm ply. I also used exterior grade plywood for the sides as this would make it more long-lasting I figured. This means you will need a little extra ply for this and luckily I had some scraps laying around. I also left out the ventilation holes as it's cooler in the UK, and added a bottom as well.

The total construction cost was around £70 but if you make them in bulk with four boxes to a full sheet of 9mm and 12mm ply, it should come down. I also added a roofing felt cap over the top to keep the rain off longer.

Tuesday, 9 July 2013

The new D500x firmware version 2.2.2 has been released. The trigger sensitivity option now allows for better rejection of noise events and there is a new timer option that can start and stop the detector relative to sunrise and sunset when you put in your latitude and longitude. Both are very welcome additions.

One of the most useful features I've found though is that the log file created during recording events shows the battery voltage through time. This really helps in choosing the right batteries for the duration the detector is used. I trialled it with an external battery case with four NiMh 'C' cells which gave out 4 x 1.2v = 4.8 V. You could see the voltage change through time until the detector got to 4.2 V when the detector stopped working. I'm sure with four alkaline C cells at a total of 4 x 1.5v = 6 V it would have been fine.

While we all want to be responsible and use rechargeables, it often just does not work with devices like this when you need them to be reliable and are not checking on the batteries all the time. Most of my NiMh AA cells are unusable after two seasons as they suddenly lose charge. I think the best power source is still a 6V lead-acid battery for long periods in the field.

I've had some lovely long-eared recordings from my D500x from a church recently, plus a load of very varied but wonderful social calls. Long-eard bats are certainly very talkative.

Friday, 3 May 2013

Well Ubuntu 13.04 'Raring Ringtail' is here, and it makes for an easy upgrade, even on a dual boot Windows 7 machine, my only gripe being that it overwrote my Windows 7 bootloader with Grub-2, the Ubuntu boot loader. Not a problem unless you decide to remove Linux in which case you won't be able to easily boot into Windows. Batsound still works well under WINE but I still haven't sorted out the graphics export problem. The dialogue appears but the resulting image files are corrupted. Not a huge problem since Ubuntu has such a versatile set of screen grabbing and editing tools. I tried out crossover which is a commercial version of WINE to install Batsound. Again, this worked fine, and now in the export graphics image dialogue box the option to export to .jpg appears but the files are still empty or corrupted. As far as I can tell, all other functions like audio capture and playback work just fine under Ubuntu.

Monday, 21 January 2013

Not much closer to a solution for the saving of sonogram images from Batsound under Linux. It seems that WINE only has limited support fir JPEG, but then .png files would arguably be better for export anyway, preserving the crisp edges of text labels. It does look like there may be a way of configuring Widows drives under WINE, so that files would not have to be in the Linux partition. That's part of the fun of Linux, problem solving....

Friday, 18 January 2013

After someone asked me about sound analysis tools under Linux at the BCT conference in York it's been on my mind. There is the excellent Audacity, but this has limited tools of interest to the bat surveyor, good though it is. I had an old and very unresponsive laptop that was struggling with Windows XP (20 minutes to boot-up - not good), so I put Linux on it, Ubuntu 12.10. The installation was not without issue, the wireless networking especially, but once it was on I had a working, fast laptop. Now for Batsound....

I was expecting a fight, but it was actually very straightforward. First from Ubuntu software center install WINE (Wine Is Not Emulator). Then right click on the Batsound.msi file. It actually says in the WINE documentation that it will not install from an .msi, but this was fine. This will install it to a virtual C drive which is actually hosted on your Linux home partition. Enter your name, organisation and the serial number and off it goes.

Batsound then appears in your list of applications (DASH in Ubuntu), click on it and it runs! Just as fast as normal. I'll report any issues I find but at the moment the only thing I have found not working is that it won't save the workspace as an image file. Also, you can't access your normal C:\ drive for files. There must be a workaround for this somehow.